Triangle

[jkswebsite]

Quote:

* Write a class called Triangle.
*
* A triangle must have three int values for its side lengths.
* These private fields MUST have names a, b, and c.
*
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
* THE FOLLOWING METHODS AND CONSTRUCTORS MUST APPEAR IN THIS ORDER! *
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
*
* Write a default constructor that creates an
* equilateral Triangle with side length 1.0
*
* Write another constructor that takes three int parameters that
* will be the three side lengths. It must validate
* the three parameters that they can actually form a triangle.
* (recall from Geometry: the sum of any two sides
* of a triangle must be greater than the third side)
* The constructor must throw an IllegalArgumentException
* if the parameters are invalid.
*
* Write a method called getLongestSide that takes no parameters
* and returns the value of the longest side length.
* (i.e. the greatest of a,b, and c)
*
* Write a method called isRightTriangle that takes no parameters
* and returns true if the Triangle, (whose sides are a,b, and c)
* form a right triangle and returns false otherwise.
* (hint: use Pythagorean Theorem and recall the longest side is the hypotenuse)
*
* Write a method called scalar that takes an int parameter and
* converts this Triangle to a similar Triangle by multiplying
* each side length by the parameter.
*
* ~~BONUS~~
* Write a method called isCongruentTo that takes a Triangle parameter
* and returns true if all three 'corresponding' sides are equal,
* and returns false otherwise.
* (example: 3,4,5 is congruent to 3,5,4 but not congruent to 3,3,5)
*
* ~~BONUS~~
* Write a method called area that returns the area of this Triangle
*
*/

... (over) ...

/**
* TriangleRunner should produce the following output shown below
*/

public class TriangleRunner {
public static void main(String args[]) {

Triangle t1 = new Triangle();
Triangle t2 = new Triangle(3,4,5);
Triangle t3 = new Triangle(4,6,3);
System.out.println(t1.longestSide());
System.out.println(t2.longestSide());
System.out.println(t3.longestSide());
System.out.println(t1.isRightTriangle());
System.out.println(t2.isRightTriangle());
System.out.println(t3.isRightTriangle());
t1.scalar(10);
t2.scalar(10);
t3.scalar(10);
System.out.println(t1.longestSide());
System.out.println(t2.longestSide());
System.out.println(t3.longestSide());
System.out.println(t1.isRightTriangle());
System.out.println(t2.isRightTriangle());
System.out.println(t3.isRightTriangle());
Triangle t4 = new Triangle(3,9,4);
}
}

/*
output:
1
5
6
false
true
false
10
50
60
false
true
false
Exception in thread "main" java.lang.IllegalArgumentException: cannot form a tri
angle with values 3,9,4
*/

That is out assignment, and I have a template and some basic starting code, but could someone walk me through it? My aim is Jkk088. I'll be on all day. Thanks so much, I really appreciate it.

[CaptainMorgan]

You've got pretty detailed instructions - there shouldn't be much confusion on your part, break out the old algebra/trig book and get started. I mean, you've even got a runner class that implies the output you're supposed to receive.. think about this for a second, how difficult can this be?

Btw, thanks for the message - but you're better off posting a thread such as you did here and chances are you'll get more responses, unless I was the only one you messaged. I'm not interested in doing other people's work, but I am interested in helping others learn the language. Your problem is not a Java problem, but a motivational problem. Why do you believe you can't do this?

[jkswebsite]

I don't really understand much java. I just need to hear what format to put it in..

(if statement..etc.)

[CaptainMorgan]

Then start here.

[jkswebsite]

this is the most recent code I have. I'M SO CLOSE!

Quote:

/**
* Class triangle
*/

public class Triangle {

private int a;
private int b;
private int c;

/**
* Default constructor that creates an equilateral Triangle with side length
* 1.0
*/

public Triangle() {
a = (int) 1;
b = (int) 1;
c = (int) 1;
}

/**
* Another constructor that takes three int parameters that will be the
* three side lengths. It must validate the three parameters that they can
* actually form a triangle. (recall from Geometry: the sum of any two sides
* of a triangle must be greater than the third side) The constructor must
* throw an IllegalArgumentException if the parameters are invalid.
* @return
*
* @return
*/

public Triangle(int d, int e, int f) {
if (d + e > f && e + f > d && f + e > d) {
a = d;
b = e;
c = f;
} else {
throw new IllegalArgumentException("cannot form a triangle with values "+ a +","+ b +","+ c);
}


}

/**
* Method called getLongestSide that takes no parameters and returns the
* value of the longest side length. (i.e. the greatest of a,b, and c)
*/

public int longestSide() {
if (a >= b && a >= c)
return a;
else if (b >= a && b >= c)
return b;
else
return c;
}

/**
* Method called isRightTriangle that takes no parameters and returns true
* if the Triangle, (whose sides are a,b, and c) form a right triangle and
* returns false otherwise. (hint: use Pythagorean Theorem and recall the
* longest side is the hypotenuse)
*/

public boolean isRightTriangle() {
if (a * a + b * b == c * c)
return true;
else
return false;
}

/**
* Method called scalar that takes an int parameter and converts this
* Triangle to a similar Triangle by multiplying each side length by the
* parameter.
*/

public void scalar(int i) {
a = a * i;
b = b * i;
c = c * i;
}

/**
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
* BONUS! * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
*
*/

{
/**
* Method called isCongruentTo that takes a Triangle parameter and
* returns true if all three 'corresponding' sides are equal, and
* returns false otherwise. (example: 3,4,5 is congruent to 3,5,4 but
* not congruent to 3,3,5)
*/

// INSERT CODE HERE
}

{
/**
* Write a method called area that returns the area of this Triangle
*/

// INSERT CODE HERE
}

}

this is the output I get:

Quote:

1
5
6
false
true
false
10
50
60
false
true
false

this is the output you're SUPPOSED to get:

Quote:

1
5
6
false
true
false
10
50
60
false
true
false
Exception in thread "main" java.lang.IllegalArgumentException: cannot form a tri
angle with values 3,9,4

Quote:

Triangle t4 = new Triangle(3,9,4);

the problem is my t4 in my TriangleRunner.java class isn't being read for some reason.

any ideas?

[jkswebsite]

I Got It!!!! Thanks!!

[CaptainMorgan]

I haven't read over your final result, but I'll assume that you got it correct and are satisfied with your work. Congratulations on figuring it out and I hope that maybe you learned that this can be fun, if not now maybe you will in the near future. Aren't you glad you figured it? Deriving the solution for oneself is typically found to be more fun than acquiring the solution from someone else.

Cheers